Handguard with Timing Pin

ABSTRACT

A handguard is attached to a M16/M4 family firearm by sliding the handguard onto the barrel nut, rotating the handguard relative to the barrel nut and then positioning a timing pin in one of the scallops of the barrel nut sprocket to lock the handguard in position. The back of the hand guard has grooves and ridged matching the barrel nuts teeth and sprockets. Rotating the handguard causes the teeth to enter into slots in the ridges to thereby prevent the handguard from pulling free. A clamping mechanism in the handguard can clamp onto the barrel nut. The addition of friction bushings attached to the inside of the handguard and behind the barrel nut sprocket can provide for even stronger retention.

RELATED APPLICATIONS

This application claims the benefit and priority of U.S. Provisional Applications 62/236,285 and 62/401,967. U.S. Provisional Application 62/236,285 was filed Oct. 2, 2015 and titled “Handguard with Timing Pin.” U.S. Provisional Application 62/401,967 was filed Sep. 30, 2016 and titled “Handguard with Timing Pin.” U.S. Provisional Applications 62/236,285 and 62/401,967 are herein incorporated by reference in their entirety.

TECHNICAL FIELD

Embodiments are related to firearm handguards, to mounting rail systems for firearms, and to free floating handguards for firearms

BACKGROUND

Many modern firearms can be easily modified by swapping various parts into and out of “the build.” One firearm family in particular, the M-4 family, has thrived and is the basis for many standard military small arms and civilian firearms. One key aspect is that different parts can be mixed and to produce a wide variety of firearms. For example, the military M-4 carbine is a small light close-quarters automatic weapon. Other M-4 family members are the civilian AR-15 and the military M-16. Some versions of the AR-15 are heavy barreled full stock rifles that are accurate out to 600 meters and beyond. Interestingly, a hobbyist with basic tools can change out components of an M-4 carbine to produce a heavy barreled AR-15 long range completion rifle.

FIG. 1, labeled as “Prior Art,” illustrates an M16 type firearm 101 with mounting rails 106. The specific rifle is a flat top model having a mounting rail 106 on the upper receiver 102 as well as the four on the handguard 105. As is standard for M16 type firearms, the handguard 105 is attached to the firearm by being pushed into a front handguard cup 104 by a delta ring 103. The illustrated handguard 101 has four non-powered mounting rails 106 of which three are visible. A number of accessories have been developed to attach to small arms by way of mounting rails 106. The mounting rails have recoil grooves that help lock accessories in place and help users attach accessories in repeatable positions. Note that the term “firearm” used here and throughout this document is intended to include firearm replicas. In general, firearm replicas are toys or models that look substantially like fully functioning firearms and are designed to accommodate the same firearm accessories as those used with fully functional firearms. As such, FIG. 1 can also be a picture of a firearm replica.

FIG. 2, labeled as “Prior Art,” illustrates a barrel nut 201 having a barrel nut sprocket 202. The barrel nut sprocket 202 has numerous teeth 203 with scallops 204 between the teeth. The teeth 202 can provide a gripping surface for turning the barrel nut 201. As is well known by those familiar with modern firearms, the barrel nut 201 attaches the barrel to the upper receiver with the barrel nut sprocket 202 toward the front, or muzzle, end of the firearm. Many current handguards are “free floating” in that they attach to the barrel nut 201 but do not touch the barrel.

FIG. 3, labeled as “Prior Art,” illustrates a barrel nut 201 attaching a barrel 301 to a firearm upper receiver 102. The barrel nut 201 is tightened onto the receiver 102 by gripping the barrel nut sprocket 202 and twisting. A special tool is often used to tighten the barrel nut 201 until the barrel nut 201 and the barrel 301 are firmly attached to the receiver 102. Notice that the barrel nut is installed with the barrel nut sprocket toward the front.

US 2015/0241166 titled “POWERED FORWARD MODULE” was filed by Hines on Mar. 13, 2013 and is herein incorporated by reference in its entirety.” US 2015/0241166 teaches a free floated handguard attached to the barrel nut of an M-4 family firearm. It is for these teachings, amongst others, that US 2015/0241166 is herein incorporated by reference in its entirety.

A variety of free floating handguards have been introduced on the market with different handguards requiring different levels of skill to install. In general, current handguards are either held by the barrel nut or clamp onto the barrel nut. Some work better than others. None are ideal. Improved systems and methods for attaching handguards to rifles and carbines are needed.

BRIEF SUMMARY

The following summary is provided to facilitate an understanding of some of the innovative features unique to the embodiments and is not intended to be a full description. A full appreciation of the various aspects of the embodiments can be gained by taking the entire specification, claims, drawings, and abstract as a whole.

It is therefore an aspect of the embodiments to attach a handguard to a firearm, the firearm having a barrel nut attaching a barrel to the firearm receiver. The barrel nut has a barrel nut sprocket with many teeth and scallops between the teeth. The back of handguard has grooves and ridges such that the handguard can be slid onto the barrel nut with the teeth sliding through the grooves and the ridges sliding through the scallops.

It is another aspect of the embodiments that there are slots in the ridges. The teeth can rotate into the slots by rotating the handguard after it is slid onto the barrel nut. The teeth in the slots prevent the handguard from sliding back off the barrel nut. A timing pin that is held in position in the handguard and in one of the scallops can prevent the handguard from rotating and the teeth from rotating out of the slots.

It is yet another aspect of the embodiments that a timing pin assembly can have a pin tab and the timing pin. The handguard can hold the timing pin assembly with the timing pin in a scallop. The handguard can have two clamp jaws with the timing pin assembly held in or relative to the clamp jaws. A front bolt passing through the clamp jaws can keep the timing pin assembly in place. One or more clamp bolts can be used to tighten the clamp jaws together and thereby cause the handguard to clamp onto the barrel nut.

It is a further aspect of the embodiments that one or more friction bushings can be attached to the inside of the handguard and behind the barrel nut sprocket, perhaps with button head screws. The friction bushing, in addition to the slots, can prevent the handguard from sliding off the barrel nut.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying figures, in which like reference numerals refer to identical or functionally similar elements throughout the separate views and which are incorporated in and form a part of the specification, further illustrate the present invention and, together with the background of the invention, brief summary of the invention, and detailed description of the invention, serve to explain the principles of the present invention.

FIG. 1, labeled as “Prior Art,” illustrates an M16 type firearm with mounting rails;

FIG. 2, labeled as “Prior Art,” illustrates a barrel nut having a barrel nut sprocket;

FIG. 3, labeled as “Prior Art,” illustrates a barrel nut attaching a barrel to a firearm upper receiver;

FIG. 4 illustrates the back end of a handguard with all bolts, screws, bushings, and the timing pin in place in accordance with aspects of the embodiments;

FIG. 5 is an exploded view of the assembly of FIG. 4 with the addition of a barrel nut in accordance with aspects of the embodiments;

FIG. 6 illustrates the back end of a handguard in accordance with aspects of the embodiments;

FIG. 7, labeled as “Prior Art,” is a rear view of a barrel nut better illustrating the teeth and scallops;

FIG. 8 illustrates the barrel nut of FIG. 7 inside the handguard of FIG. 6 in accordance with aspects of the embodiments;

FIG. 9 illustrates the alignment of the barrel nut, pin tab, timing pin, and front bolt when the handguard is installed on a firearm in accordance with aspects of the embodiments; and

FIG. 10 illustrates a handguard properly installed on a barrel nut in accordance with aspects of the embodiments.

DETAILED DESCRIPTION

The particular values and configurations discussed in these non-limiting examples can be varied and are cited merely to illustrate at least one embodiment and are not intended to limit the scope thereof. In general, the figures are not to scale.

A handguard is attached to a M16/M4 family firearm by sliding the handguard onto the barrel nut, rotating the handguard relative to the barrel nut and then positioning a timing pin in one of the scallops of the barrel nut sprocket to lock the handguard in position. The back of the hand guard has grooves and ridged matching the barrel nuts teeth and sprockets. Rotating the handguard causes the teeth to enter into slots in the ridges to thereby prevent the handguard from pulling free. A clamping mechanism in the handguard can clamp onto the barrel nut. The addition of friction bushings attached to the inside of the handguard and behind the barrel nut sprocket can provide for even stronger retention.

FIG. 4 illustrates the back end 402 of a handguard 401 with all bolts 411, 412, screws 501, bushings 413, and the timing pin in place in accordance with aspects of the embodiments. The handguard 401 is designed to be slipped onto the barrel nut 201, rotated a few degrees, and then fixed in place. The timing pin and bushings 413 should not be in place when attempting insert the barrel nut into the handguard. There are two clamp bolts 411 positioned in the clamping section 409 at the back end 402 of the handguard 401. Tightening the clamp bolts 411 causes the gap 408 between the clamp jaws 407 to narrow and the handguard 401 to clamp onto the barrel nut 201. The front bolt 412 is primarily for keeping the pin tab 410 and timing pin in position. The slots 406 are wide enough that the barrel nut teeth 203 can fit in the slot 406 when the handguard 401 is rotated on the barrel nut 201. When the barrel nut 201 is slid into the handguard 401, the teeth 203 of the barrel nut 201 slide into grooves 405 in the handguard and the ridges 403 in the handguard 401 slide in the scallops 204 of the barrel nut.

FIG. 5 is an exploded view of the assembly of FIG. 4 with the addition of a barrel nut 201 in accordance with aspects of the embodiments. Notice that the barrel nut teeth 203 are not aligned with the handguard grooves 405 such that the handguard can slip over the barrel nut. Instead the handguard 401 must be rotated a few degrees, slipped onto the barrel nut 201, and then rotated back so the teeth 203 are in the slots 406. The barrel nut teeth 203 fit into the slots 406 of FIG. 4 when the handguard 401 is rotated a few degrees. Note that the bolts 411, 412 and screws 501 are depicted without threads. It is understood that the bolts and screws do have threads and that the friction bushings 413 and clamping section 409 are properly threaded to receive then.

FIG. 6 illustrates the back end 402 of a handguard 401 in accordance with aspects of the embodiments. FIG. 6 provides a good view of the grooves 405, ridges 403, clamp jaws 407, and the gap 408 between the clamp jaws 407.

FIG. 7, labeled as “Prior Art,” is a rear view of a barrel nut 201 better illustrating the teeth 203 and scallops 204.

FIG. 8 illustrates the barrel nut 201 of FIG. 7 inside the handguard 401 of FIG. 6 in accordance with aspects of the embodiments. Notice that in FIG. 8, the barrel nut teeth 203 are positioned in the slots 406 and that the barrel nut 201 cannot be pulled out of the handguard 401 without first rotating the handguard 401 a few degrees. Another element that keeps the barrel nut 201 from sliding free is the friction bushings 413, as seen in FIGS. 5, 10. The timing pin 502 can be seen position in a scallop 204 to prevent the handguard 401 and barrel nut 201 from rotating relative to one another. As such, the barrel nut 201 can't be slid from the handguard 401 without first removing the timing pin 502 and rotating the teeth 203 out of the slots 406.

FIG. 9 illustrates the alignment of the barrel nut 201, pin tab 410, timing pin 502, and front bolt 412 when the handguard 401 is installed on a firearm in accordance with aspects of the embodiments. The front bolt 412 is keeping the timing pin assembly 801 in position while the timing pin 502 is in one of the scallops 204. The timing pin assembly 801 is a piece including the timing pin 502 and pin tab 410.

FIG. 10 illustrates a handguard 401 properly installed on a barrel nut 201 in accordance with aspects of the embodiments. Notice that FIG. 10 is, in essence, FIG. 4 but with a barrel nut 201 in place. Screws 501 attach friction bushings 413 to the inside of the handguard 401 and behind the barrel nut sprocket 202. The timing pin cannot be seen but is in position because pin tab 410 of the timing pin assembly 801 can be seen where it is held in position by front bolt 412. Clamp bolts 411 are pressing clamp jaws 407 together to thereby cause the handguard 401 to clamp onto the barrel nut 201.

It will be appreciated that variations of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. 

What is claimed is:
 1. A handguard for a firearm, the firearm comprising a barrel nut attaching a barrel to a receiver, wherein the barrel nut comprises a barrel nut sprocket, and wherein the barrel nut sprocket comprises a plurality of teeth and a plurality of scallops between the teeth, the handguard comprising: a handguard body having a front end and a back end wherein the back end comprises a plurality of grooves and ridges, wherein a plurality of the teeth enter into a plurality of the grooves when the barrel nut sprocket enters the back end, and wherein a plurality of the ridges enter into a plurality of the scallops when the barrel nut sprocket enters the back end; a plurality of slots in the ridges wherein at least one of the teeth enter into at least one of the slots when the handguard is rotated relative to the barrel nut after the barrel nut sprocket is inserted into the back end, and wherein the at least one of the teeth that is in at least one of the slots prevents the barrel nut sprocket from sliding out of the back end; a timing pin assembly comprising a timing pin and a pin tab; two clamp jaws and a gap, wherein the timing pin assembly is retained relative to the two clamp jaws such that the timing pin is located in one of the scallops and prevents the handguard from rotating relative to the barrel nut; a clamp bolt wherein tightening the clamp bolt causes the two clamp jaws to draw together and causes the handguard to clamp onto the barrel nut; a front bolt wherein the front bolt passes through the two clamp jaws and wherein the front bolt retains the timing pin assembly relative to the two clamp jaws; and a friction bushing wherein the friction bushing is positioned behind the barrel nut sprocket and attached to and inside the handguard, and wherein the friction bushing prevents the barrel nut from pulling free of the handguard.
 2. A handguard for a firearm, the firearm comprising a barrel nut attaching a barrel to a receiver, wherein the barrel nut comprises a barrel nut sprocket, and wherein the barrel nut sprocket comprises a plurality of teeth and a plurality of scallops between the teeth, the handguard comprising: a handguard body having a front end and a back end wherein the back end comprises a plurality of grooves and ridges, wherein a plurality of the teeth enter into a plurality of the grooves when the barrel nut sprocket enters the back end, and wherein a plurality of the ridges enter into a plurality of the scallops when the barrel nut sprocket enters the back end; and a plurality of slots in the ridges wherein at least one of the teeth enter into at least one of the slots when the handguard is rotated relative to the barrel nut after the barrel nut sprocket is inserted into the back end, and wherein the at least one of the teeth that is in at least one of the slots prevents the barrel nut sprocket from sliding out of the back end.
 3. The handguard of claim 2 further comprising: a timing pin assembly comprising a timing pin and a pin tab; and two clamp jaws and a gap between the two clamp jaws, wherein the timing pin is retained between the two clamp jaws, wherein the timing pin is located in one of the scallops and prevents the handguard from rotating relative to the barrel nut.
 4. The handguard of claim 2 further comprising: a timing pin assembly comprising a timing pin and a pin tab; and two clamp jaws and a gap between the two clamp jaws, wherein the timing pin assembly is retained relative to the two clamp jaws such that the timing pin is located in one of the scallops and prevents the handguard from rotating relative to the barrel nut.
 5. The handguard of claim 4 further comprising a clamp bolt wherein tightening the clamp bolt causes the two clamp jaws to draw together and causes the handguard to clamp onto the barrel nut.
 6. The handguard of claim 5 further comprising a front bolt wherein the front bolt passes through the two clamp jaws and wherein the front bolt retains the timing pin assembly relative to the two clamp jaws.
 7. The system of claim 6 further comprising a friction bushing wherein the friction bushing is positioned behind the barrel nut sprocket and attached to and inside the handguard, and wherein the friction bushing prevents the barrel nut from pulling free of the handguard.
 8. The handguard of claim 2 further comprising a clamp bolt and two clamp jaws wherein tightening the clamp bolt causes the two clamp jaws to draw together and causes the handguard to clamp onto the barrel nut.
 9. The system of claim 2 further comprising a friction bushing wherein the friction bushing is positioned behind the barrel nut sprocket and attached to and inside the handguard, and wherein the friction bushing prevents the barrel nut from pulling free of the handguard.
 10. The handguard of claim 9 further comprising a clamp bolt and two clamp jaws wherein tightening the clamp bolt causes the two clamp jaws to draw together and causes the handguard to clamp onto the barrel nut.
 11. The system of claim 2 further comprising two friction bushings wherein the two friction bushings are positioned behind the barrel nut sprocket, wherein the two friction bushings are attached to and inside the handguard and diagonally opposed to one another, and wherein the friction two bushings prevents the barrel nut from pulling free of the handguard.
 12. A method for attaching a handguard to a firearm, the firearm comprising a barrel nut attaching a barrel to a receiver, wherein the barrel nut comprises a barrel nut sprocket, and wherein the barrel nut sprocket comprises a plurality of teeth and a plurality of scallops between the teeth, the method comprising the steps of: sliding the handguard onto the barrel nut wherein the barrel nut sprocket enters a back end of the handguard, wherein the back end comprises a plurality of grooves and ridges, wherein a plurality of the teeth enter into a plurality of the grooves when the barrel nut sprocket enters the back end, and wherein a plurality of the ridges enter into a plurality of the scallops when the barrel nut sprocket enters the back end; and rotating the handguard relative to the barrel nut after sliding the handguard onto the barrel nut wherein the handguard comprises a plurality of slots in the ridges, wherein at least one of the teeth enter into at least one of the slots when the handguard is rotated relative to the barrel nut, and wherein the at least one of the teeth that is in at least one of the slots prevents the barrel nut sprocket from sliding out of the back end.
 13. The method of claim 12 further comprising the step of: retaining a timing pin in the handguard wherein the handguard holds the timing pin in one of the scallops and prevents the handguard from rotating relative to the barrel nut.
 14. The method of claim 12 further comprising the step of: retaining a timing pin assembly relative to two clamp jaws, wherein the handguard comprises the two clamp jaws, wherein the timing pin assembly comprises a timing pin and a pin tab, wherein the timing pin is located in one of the scallops and prevents the handguard from rotating relative to the barrel nut.
 15. The method of claim 14 further comprising the step of: tightening clamp bolt wherein tightening the clamp bolt causes the two clamp jaws to draw together and causes the handguard to clamp onto the barrel nut.
 16. The method of claim 15 further comprising the step of: passing a front bolt through the two clamp jaws wherein the front bolt retains the timing pin assembly relative to the two clamp jaws.
 17. The method of claim 16 further comprising the step of: attaching a friction bushing inside the back end and behind the barrel nut sprocket wherein the friction bushing prevents the barrel nut from pulling free of the handguard.
 18. The method of claim 12 further comprising the step of: clamping the handguard to the barrel nut wherein the handguard comprises two clamp jaws wherein tightening a clamp bolt causes the two clamp jaws to draw together and causes the handguard to clamp onto the barrel nut.
 19. The method of claim 12 further comprising the step of: attaching a friction bushing inside the back end and behind the barrel nut sprocket wherein the friction bushing prevents the barrel nut from pulling free of the handguard.
 20. The method of claim 19 further comprising the step of: clamping the handguard to the barrel nut wherein the handguard comprises two clamp jaws wherein tightening a clamp bolt causes the two clamp jaws to draw together and causes the handguard to clamp onto the barrel nut. 